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991.
Shawler DL Bartholomew RM Garrett MA Trauger RJ Dorigo O Van Beveren C Marchese A Ferre F Duffy C Carlo DJ Sherman LA Gold DP Sobol RE 《Clinical and experimental immunology》2002,127(1):99-106
In the present prospective, census-based study we have investigated the prevalence of organ-specific and non-organ-specific autoantibodies (AAb) in 152 unselected Cameroonians aged 60 years and older living in the community. AAb were detected in 49% of the participants. Non-organ-specific AAb (47%) predominated over organ-specific AAb (7%). Anti-TPO, anti-Tm, anti-Tg and anti-PC AAb were completely absent. RF was the most frequent AAb, being found in 57 (38%) cases. The prevalences of anti-SMA and RF were significantly higher in women than in men (respectively, P=0.023 and P=0.016). Higher serum concentrations of gammaglobulins were accompanied by a higher prevalence of RF (P < 0.0001) and a lower prevalence of ANA (P=0.036). The overall prevalence of AAb was higher in the filaria-infected (60%) compared to the non-infected (42%) participants (P=0.046). There was no significant influence of the vitamin D status, number of pregnancies, physical activity or medication use on the prevalence of AAb. In this study a heterogeneous pattern for the presence of the various AAb was found. Some AAb, which are commonly encountered in other studies on elderly subjects, were completely absent in this population. This diversified pattern of AAb prevalence therefore argues in favour of exogenous influences in the occurrence of AAb in elderly populations. 相似文献
992.
Trimoulet P Neau D Le Bail B Rullier A Winnock M Galperine T Legrand E Schvoerer E Dupon M Ragnaud JM Bioulac-Sage P Chêne G Fleury H Lafon ME 《Journal of medical virology》2002,67(2):143-151
Serum and intrahepatic hepatitis C virus (HCV) RNA were measured in 37 HIV-HCV co-infected patients with controlled human immunodeficiency virus (HIV) infection and correlated with clinical, biological, and histological parameters. Thirty-seven interferon-naive patients underwent liver biopsy. HCV-induced activity (A) and fibrosis (F) were evaluated with METAVIR score. The 37 patients included had HIV plasma loads < 10,000 copies/ml, CD4(+) count > 250/microl. All the patients but two were receiving antiretroviral treatment. Liver tissue and sera were used for measurement of HCV RNA by the Cobas Amplicor HCV Monitor. All patients had serum and liver HCV RNA, and both levels were correlated (r = 0.47; P = 0.003). Intrahepatic HCV load did not depend on age, sex, duration of HCV infection, CD4(+), HCV genotype, or fibrosis. AST levels correlated with intrahepatic HCV load (r = 0.52; P = 0.001). Patients with METAVIR A1/A2 had significantly lower levels of liver HCV-RNA than were found in patients with METAVIR A3 (P = 0.026). Highly active antiretroviral therapy (HAART) including protease inhibitors(PI)-treated patients had significantly lower intrahepatic HCV load (P = 0.04). A weak but significant correlation between serum and liver HCV RNA was found. The amount of hepatic HCV RNA was correlated with AST levels, histological activity, but not with HCV genotype or fibrosis. The immune improvement associated with PI regimens could help reduce HCV load, supporting a protective effect of PI-induced immune restoration. 相似文献
993.
Tobiasch E Kehm R Bahr U Tidona CA Jakob NJ Handermann M Darai G Giese M 《Virus genes》2001,22(2):187-199
Equine arteritis virus (EAV) is a member of the Arteriviridae family, that includes lactate dehydrogenase-elevating virus (LDV), porcine reproductive and respiratory syndrome virus (PRRSV), and simian haemorrhagic fever virus (SHFV). Equine arteritis is a contagious disease of horses and is spread via respiratory or reproductive tract. The objective of the present study is to evaluate the possibility for developing a model system for prevention horses against an EAV infection by DNA vaccination. A cDNA bank from the RNA of EAV was established. This gene library contains the translation unit of the EAV open reading frames (ORF) 1 to 7. The identity of the cDNA was confirmed by nucleotide sequence analysis. Using this defined EAV cDNA gene library the cDNA sequence of the viral ORFs were molecularly cloned into the corresponding sites of well characterized and powerful expression vectors (pCR3.1, pDisplay, and/or pcDNA3.1/HisC).The capability of these recombinant plasmids expressing the gene products of the individual viral ORFs 3 to 5, and 7 in induction of an immune response in mouse system was investigated. The Balb/c mice (ten mice per assay) were inoculated with the DNA of the constructed expression vectors harboring and expressing the EAV cDNA of the viral ORFs. The Balb/c mice were injected with about 100 g DNA diluted in 100 l PBS. The DNA was injected subcutaneously and into the tibialis cranialis muscle (Musculus gastrocnemius). The mice were boosted 3 to 5 times with the same quantities of DNA and under the same conditions at about two week intervals. Control mice received the same amount of parental expression vectors via an identical route and frequency.The pre- and post-vaccinated sera of the individual animals were screened by neutralization tests (NT). Neutralizing antibodies against EAV were detected when the animals were inoculated with the DNA of the expression vectors harboring cDNA of the EAV ORFs 5 and 7. Highest NT-titers were observed when the animals were administered with the cDNA of ORF 5 and/or with the cDNA of the neutralization determinants of EAV that is located on the N-terminal ectodomain of the gene product of ORF 5 between the amino acid positions 1–121. These results obtained from these studies justified proofing the capability of the EAV cDNA sequences of the viral genes including ORFs 5 and 7 in the autologous animal system horse. 相似文献
994.
In some patients with chronic liver disease induced by hepatitis B virus, viral DNA is known to persist in low concentration in serum after seroconversion to hepatitis B surface antibody-positivity. This phenomenon has, however, not been documented in asymptomatic black African carriers of hepatitis B virus. Using nested amplification by the polymerase chain reaction, we detected low concentrations of hepatitis B virus DNA in the serum of 6 of 23 (26%) healthy black African adults with normal liver function and with hepatitis B virus surface antibody as the only serological marker of the virus. This finding offers one explanation for the earlier observation of integrated hepatitis B virus DNA in hepatocellular carcinomas in black Africans whose serum was positive for surface antibody alone. A number of genetic changes were found in the six isolates that might be responsible for evasion of the immune response and persistence of the virus. Isolated mutations were detected in the "a" determinant of the surface gene and in the encapsidation signal. In all five isolates sequenced in the core promoter, mutations were present in the upstream regulatory region. Recombination between genotypes A and D was present in three of the isolates, including both of those in which the entire genome was sequenced. This change in genotype also overlapped the amino end of the polymerase domain and may result in sufficiently low levels of replication to allow viral persistence. Topoisomerase 1 specific trinucleotides were concentrated in the vicinity of the recombination breakpoints. 相似文献
995.
ObjectiveTo
understand the mechanism of liver cirrhosis after the infection of hepatitis B virus.MethodsMouse
fibroblast NIH3T3 cells were transfected with 3.2 kb HBV DND by exposure of the cells to
calcium phosphate.The change of the levels of mRNA for tissue inhibitor of
metalloproteinase 1and 2(TIMP1,2) was detected in mouse fibroblast NIH3T3 cells and the cells of transfection
with HBV Genome by in situ hybridization.ResultsThe levels of mRNA for
TIMP1 and TIMP2 were increased significantly.ConclusionHBV infection can
induce the expression of the mRNA for TIMP1 and TIMP2. 相似文献
996.
Umemura T Yoshizawa K Ota M Katsuyama Y Inada H Tanaka E Kiyosawa K 《Clinical and experimental immunology》2000,121(1):120-126
Many T cells infiltrate into the liver of patients with chronic hepatitis C (CH-C). They are believed to play a crucial role in the immunopathogenesis of hepatic inflammation, but their clonality and specificity are unknown. The aim of this study was to clarify the characteristics of these T cells. We analysed the complementarity-determining region (CDR)3 size lengths of T cell receptor (TCR) beta-chains by size spectratyping, and determined the sequences of Vbeta CDR3 after subcloning Vbeta-specific polymerase chain reaction products. Spectratyping showed clonal expansions in all liver specimens, most of which showed more than two T cell clones. Moreover, many non-clonal T cells also accumulated in the liver. Clonality of the T cells suspected by spectratyping was confirmed by CDR3 sequencing. Although the sequences revealed no whole CDR3-shared clones among different patients, some common motif sequences were observed. Our data suggest that T cells are stimulated by several hepatitis C virus (HCV) epitopes, then accumulate in the liver of CH-C patients. Shared motifs of expanded T cell clones suggest that they might recognize the same regions of HCV peptides, but have differences due to HCV peptide mutational changes. These clones might also interact with non-clonal T cells and play a crucial role in the immunopathogenesis of CH-C. 相似文献
997.
AIMS: The causal relationship of H. pylori gastric colonization with gastric cancer development has not as yet been fully elucidated. The prevalence of H. pylori infection increases with age in the asymptomatic population in Japan, and reaches a high plateau in those older than 40 years. The objective of this study was to assess the link between H. pylori and gastric carcinomas in patients younger than 40 years. METHODS AND RESULTS: Detection of H. pylori and assessment of background mucosa based on the Sydney system was performed histopathologically for 40 Japanese gastric cancer cases younger than 40 years and compared with 40 age- and sex-matched controls. H. pylori infection in gastric mucosa was detected significantly more frequently (P < 0.001) in patients with cancer (29/40; 72.5%) than in controls (11/40; 27.5%). Additionally, by histopathological comparison between intestinal (18 cases) and diffuse (70 cases) types of young gastric cancer patients, mucosal atrophy and intestinal metaplasia were found to coexist with acute and chronic inflammation in the background mucosa of both intestinal and diffuse types, being significantly more prevalent than in young controls. CONCLUSIONS: As well as the high prevalence of H. pylori in young subjects with gastric cancer, it is clear that persistent infection induces mucosal damage, resulting in atrophy and intestinal metaplasia. Thus, acute/chronic gastritis could play an essential role in the early development of neoplasia in the stomach. 相似文献
998.
2004年中国甲3亚型流感病毒(H3N2)抗原性及基因特性研究 总被引:8,自引:0,他引:8
目的阐明2004年中国流行的甲3亚型流感病毒血凝素抗原性及其基因变异情况。方法对2004年分离的甲3亚型毒株先进行单向血凝抑制试验及交叉血凝抑制试验;在此基础上选取不同时间、地点的甲3亚型流感毒株进行血凝素基因HA1区核苷酸序列测定并推导出其氨基酸序列,然后进行基因进化特性分析。结果单向血凝抑制实验结果表明,2004年共有52.3%毒株与A/Fujian/411/2002(H3N2)(20042005毒株)有4倍或以上的血凝抑制滴度差异,交叉血凝抑制实验结果表明,它们间的抗原比为4。HA1区核苷酸序列和氨基酸序列分析表明,我国从2004年2月分离的甲3亚型毒株开始出现了与A/Fujian/411/2002(H3N2)和A/Wellington/1/2004(H3N2)(2005年国际代表株)相比较,在其HA1蛋白分子上存在有4个氨基酸位点(159位Y>F,189位S>N,145位K>N,226位V>I)发生了替换。此类毒株首发于我国南方,然后到我国北方。结论我国2004年2月份以后所分离的甲3亚型流感毒株已经发生抗原性及基因特性的改变。 相似文献
999.
原发性肝细胞癌中5种细胞周期蛋白的表达及其临床意义 总被引:4,自引:0,他引:4
目的探讨原发性肝细胞癌中5种细胞周期蛋白(cyclin)的表达及其与肝癌细胞的增殖状态、侵袭转移和乙型肝炎病毒(HBV)感染的相关性。方法应用Instrumedics公司生产的组织芯片制作仪,将273例原发性肝癌组织、144例癌旁肝组织和10例尸检非肝病死亡肝组织制成组织芯片,取样针直径2.0am,采用免疫组织化学方法分别检测了cyclin A、cyclin B、cyclin D1、cyclin D3及cyclin E在肝癌、癌旁肝及尸检肝组织的表达率,并分析了肝癌、癌旁肝组织中HBV感染与这5种cyclin表达间的相关性。结果共获得3个肝癌组织芯片蜡块,分别含136、143和148个位点。在273例肝癌组织标本中5种cyclin的阳性表达率分别为cyclin A 52.7%、cyclin B 45.4%、cyclin D1 35.9%、cyclin D3 44.3%和cyclin E 23.1%;在144例癌旁肝组织中分别为8.3%、5.6%、4.9%、6.3%和1.4%;10例尸检肝组织除1例cyclin D1阳性外,其余均为阴性。5种cyclin在肝癌组织中的阳性表达率均显著高于癌旁肝组织(P<0.01);组织学分级为Ⅱ、Ⅲ级的肝癌组织5种cyclin的表达高于Ⅰ级(P<0.05);除cyclinA外,伴有门静脉癌栓组的阳性率高于无癌栓组(P<0.01);HBV感染与cyclin的表达无明显相关性(P>0.05)。结论各个cyclin在肝癌细胞中呈不同程度的高表达,使癌细胞周期缩短,处于细胞增殖活跃状态,并有利于肝癌细胞的侵袭转移;未发现与HBV感染有关。 相似文献
1000.
Alexandersen S Quan M Murphy C Knight J Zhang Z 《Journal of comparative pathology》2003,129(4):268-282
Foot-and-mouth disease virus (FMDV) can be spread by a variety of mechanisms and the rate of spread, the incubation period and the severity of disease depend on a multitude of parameters, including the strain of virus, the dose received, the route of introduction, the animal species and the husbandry conditions. More knowledge with regard to these parameters is urgently needed to improve resource-efficient disease control. This report describes detailed studies of FMDV load, excretion and transmission in pigs infected with FMDV O UKG 2001, O TAW 1997 and C Noville virus and in cattle infected with the O UKG 2001 virus to facilitate use of a "FMDV load framework" for the assessment of transmission risks. Virus replicated rapidly in pigs and cattle exposed by direct contact. The mean incubation period was around 3-4 days for cattle-to-cattle and 1-3 days for pig-to-pig transmission, depending on the intensity of contact. The results confirmed that a strong relation exists between dose and length of incubation period. Clinical disease was severe in pigs but relatively mild in inoculated cattle; contact infection of cattle appeared to increase the severity of lesions. FMDV RNA was recovered in nasal and mouth swabs from inoculated animals soon after they developed a viraemia and probably reflected the early production and excretion of virus. FMDV RNA in nasal and mouth swabs from contact animals could be detected several days before they showed other signs of infection, indicating the possibility of detecting exposed animals during the incubation period. FMDV RNA could also be detected in swab samples after the viraemic phase. This may have represented background environmental virus that had been trapped in the respiratory tract and mouth. Alternatively, it may have indicated a somewhat slower clearance or half-life of viral RNA or an extended low level of FMDV replication at these sites. The pattern of FMDV RNA concentrations in pigs was closely similar to that in cattle, but the amounts of FMDV RNA were higher. 相似文献